AFP - More than five million children are threatened by famine in war-torn Yemen as prices soar, a charity said Wednesday, warning an entire generation may face death and "starvation on an unprecedented scale".

The three-year conflict between Yemen's Saudi-backed government and Huthi rebels linked to Iran has pushed the already impoverished country to the brink of famine, leaving many unable to afford food and water.

"Millions of children don't know when or if their next meal will come," said Helle Thorning-Schmidt, head of Save the Children International.

"This war risks killing an entire generation of Yemen's children who face multiple threats, from bombs to hunger to preventable diseases like cholera."

The already dire humanitarian situation is being exacerbated by the battle for the lifeline port of Hodeida, which is threatening what little aid is trickling into the country.

"Any disruption to food and fuel supplies coming through Hodeida port could cause starvation on an unprecedented scale," said Save the Children.

Located on Yemen's Red Sea coast, the port city of Hodeida is controlled by the rebels and blockaded by Saudi Arabia and its allies.

At a hospital in Abs, north of Hodeida, skeletal children cried as they were tended to and weighed by doctors and nurses, an AFP photographer reported.

Aid agencies have sounded the alarm over escalating violence between the Huthis and Saudi-led government alliance, which is now edging towards Hodeida after a UN attempt to bring warring parties to the negotiating table this month failed.

"The humanitarian situation is very fragile," David Miliband, head of the New York-based International Rescue Committee, told AFP as he wrapped up a visit to Yemen on Wednesday.

"My takeaway in three days in Yemen is that the humanitarian imperative doesn't just demand better flow of goods and better access for humanitarian workers," said the former British foreign secretary.